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    <script>
        var arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
        //a=1 , b=2  3
        //a=3 , b=3  6
        //a=6 , b=4  10
        //...以此类推
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            return a + b;
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        console.log("result=",result);
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